Johnson has been linked with the vacant Scotland head coach job on an interim basis after Andy Robinson stepped down from the post in the aftermath of their loss to Tonga. And if he manages to secure the job on a full-time basis and leads Scotland into the rugby showpiece in 2015, he will come up against the current second favourites for the title, South Africa.

But Johnson is adamant that Scotland could surprise the Boks if they play to their potential. "We've shown form in the last few years that proves we can take the scalps of the big teams," Johnson said. "Trying to determine what theirs or our side will look like in three years time is like determining how big, fat and ugly I'll be in three years time, which isn't easy.

"The fact is if we get our parts completely right, we'll take on anyone on any given day. That's what we're aiming to do."

With South Africa expected to top Pool B, Scotland and Samoa will battle it out for the runners-up spot with Australia, England or Wales waiting in the quarter-finals. But Johnson refused to identify the South Sea Islanders as the pivotal match and believes it will be the most competitive tournament yet.

"I remember going for the draw for the 2003 World Cup and it was obvious the pools were very weak below the first and second teams," he said. "But looking at the pools for 2015, the third, fourth and fifth teams won't be easy. Japan will be in our pool and in three years' time they will be very good.

"If you take your eye off the ball and look at just one fixture it's not fair on the tournament nor the game. We've got to do our part and do it well. If we do that we'll pull through."

Johnson's sentiments were echoed by South Africa captain Jean de Villiers, who believes Scotland will benefit from the World Cup being hosted by England. "Being used to the conditions definitely gives Scotland an advantage," De Villiers said. "It's not too far from home for them so they'll have a lot of support. We've had Samoa in every World Cup we've played. That will be another tough one.

"World rugby is getting closer and closer together and the guys are getting more competitive so by the time we hit 2015 it will be a great show for world rugby."